L=100e-6;
C=33e-12;
w0 = 1/sqrt(L*C);
f0 = w0 / 2 / pi;
T = 1 / (100*f0);
t = 0:T:(10 * 1/f0);
lt = length(t);
E=sin(w0*t);
U=E;
figure(1);
plot(t,U);
xlabel('t');
ylabel('U');

f=0:1:100;
figure(2);
plot(f, ones(size(f)));
xlabel('f');
ylabel('U');

N=100;
X=randn(1,lt);
U=X;
figure(3);
plot(U);
plot(t,X,t,U);
xlabel('t');
ylabel('U');
